Switch or control arrangement for operating x-ray apparatus



F. DESSAUER ET AL 2,181,775 SWITCH OR CONTROL ARRANGEMENT FOR OPERATINGX-RAY APPARATUS Nov. 278, 1939.

Filed Aug. 17, 1937 2 Sheets-Sheet 1 33 IPICT/F/fff um- BAT/$721K E NOV.28, 1939. F DESSAUER ET 2,181,775

SWITCH OR CONTROL ARRANGEMENT FOR OPERATING X-RAY APPARATUS Filed Aug.17, 1937 2 Sheets-Sheet 2 k /V 4/ 46 6f /a/ v w 297 A9 Patented Nov. 28,1939 'SWITGH OR-CONT-ROL ARRANGEMENT FOR OPERATING X-RAY APPARATUSFriedrich Dessauer and Kurt Lion, Istanbul,

Turkey Application August 1'7,

In Germany I I 16 Claims.

to action'by the main switch.

Switch or control arrangements of this kind of adjustment include thedanger'of a great number of errors or rather false adjustments.Furthermore they'necessitate a highly trained operating person. In spiteof the presence of such a person it may, however, happen that either themost favorable operating conditions are not followed orwhich is by farmore disagreeablethat the X-ray tube or the apparatus are overchargedandthereby damaged or even destroyed.

A great number of-switch or control arrangements are already known, bywhich the possibilities of failures are supposed to be eliminated, or atleast minimized. One means consists. in reducing the possibilities ofadjustment, thus limiting their free choice. The other retains the fulladaptability at the expense of considerable complications.

The invention is based on the fact that in practice the same organ isalways exposed with the same basic adjustments. For instance aradiograph of the lugs--once the most favorable adjustments have beenestablished-is always made with the self same basic adjustments. Suchbasic adjustments require only slight variations in respect of the smalldifierences of the particular cases in hand.

The switch or control arrangement for the working of X-ray apparatusaccording to the present invention comprises a basic device to becontrolled by an additional, co-operating control device when combinedwith said latter device, said basic device being adapted to adjust orfix automatically a plurality of important working factors whenco-operating with the control device, and a plurality of additionalcontrol devices differing from one another, each of said control devicesbeing adapted to a group of typical working conditions of the X-rayapparatus to be operated and to be easily connected with-and detachedfrom the basic device.

The basic device may be constructed in the form of a control desk.

"The control of the basic device by means of the additional controldevices maybe effected 1937, Serial No. 159,520 April 27, 1937mechanically. In such a case the additional control devices areconstructed in such a manner as to determine positions or ranges ofpositions of movable members on the basic device for adjusting thecurrent of the X-ray tube, its anode potential, the duration oftheexposure and so on. In this form of execution it is advisable thatthe basic device be fitted with driving means by which the adjustablemembers of the basic device may be moved automatically to thosepositions or to-the limits of the ranges of the positions which aredetermined by each of the additional control devices. The driving meansmay consist in a small electromotor or electromagnets and so on. For thesame purpose, however, also a driving device workable by hand could beused. The forms of execution, however, are preferable in which thecontrol of the basic device by the additional control devices is carriedout electrically. For this purpose the basic device and the additionalcontrol devices are provided with contact means which correspond to andcooperate with one another, and the contact means of the additionalcontrol devices are associated with connections mounted inside thecontrol devices and adapted in-each case to a group of typical workingconditions. The contact means of the control devices may, for instance,short-circuit different parts of circuit elements possessing steps andbeing mounted in the basic device, such as resistances, choking-coils,auto-transformers and so on. In another embodiment of the invention inwhich the control of the basic device is also effected electrically byadditional-control devices, the basic device is provided with circuitelements possessing steps, such as resistances, chokingcoils,auto-transformers-and so on, and the control devices are fitted withcontact arrangements co-operating with these circuit elements thecontact arrangement of each'control device being adapted to a' group oftypical working conditions. The contact arrangements of the controldevices may for instance be formed by more or less long longitudinalmetalmembers which short-circuit a greater or lesser number of turns orwindings of auto-transformers beingmounted in the basic device, thuscontrolling the basic device in the desired manner.

Controlling means for operating X-ray apparatus are already known whicharebased, like the present invention, on the fact of experience, that insimilar-cases of diagnostics and therapy the same group of typicalworkingconditionsshould be present. It is, for instance, already knownto provide on a movable axis a number of control disks which have radialextensions, each of these disks serving to adjust one of the workingconditions. The radial extensions act like camshafts on levers forcontrolling the voltage of the X-ray tube, its amperage, the time ofexposure and so on. This apparatus, however, did not meet with anyapproval owing to the deficiencies connected with it.

Furthermore, apparatus are known in which by means of plugs variousconnections between circuit elements being mounted in a table-likecasing may be carried out. These apparatus which show some relationshipwith the apparatus according to the present invention have, however, thegreat drawback that their use calls for a very considerable reduction ofthe number of groups of working conditions. twenty-five diiferentadjusting combinations must be efiected. This, however, is not possiblewith the apparatus referred to above for reasons of construction.Moreover, these apparatus are subjected to a number of other importantdeficiencies.

In using an apparatus being constructed according to the presentinvention the adjusting is effected very quickly, which in case of thephysician is heavily burdened or the apparatus is hard worked or, inaccident diagnostics is of vital importance. A further advantage is theabsolute reliability of adjustment. As a rule various knobs have nolonger to be turned, neither is it necessary to operate various plugs,switches or the like, which may lead to confusion, but by insertion of adefinite control device in a certain place of the apparatus all or anumber of adjustments are effected. A further very essential advantageis the fact that all possibility of faulty manipulation of the apparatusis eliminated without sacrifice in any way of accuracy of results. Onthe other hand, when using an apparatus according to the presentinvention there is no call for strict adherence to working conditionsonce the machine has been properly standardized, but by interchange ofthe control devices or modification of same the adjustments may beadapted to special circumstances. But in addition to all that, theconstruction of the X-ray apparatus itself may also be considerablysimplified as will be seen from the following: The voltage being appliedon an X-ray apparatus decreases when the load increases. Since whenassembling a control device both amperage and voltage are known, thedrop of the voltage can be taken into account and compensated alreadywhen dimensioning or designing the control device. The adjustment of thevoltage may thus be efiected by very simple means, for instance by aresistance. In an apparatus of this kind a number ofmeasuring-instruments may be spared, as these instruments with theconstructions known hitherto served chiefly for verifying thecorrectness of the adjustment.

The drawings show diagrammatically some embodiments of the invention.

Fig. 1 shows in cross section a part of a basic device and of a controldevice connected with it.

Fig. 2 shows in cross section another modification of a basic device anda control device. In

Fig. 3 an additional adjusting arrangement is shown diagrammatically.

Fig. 4 shows a basic device which it fitted with two control devices.

Fig. 5 is the wiring diagram of a time switch for producinginstantaneous Riintgenograms by means of an apparatus according to thepresent invention.

In practice at least.

Fig. 6 shows the characteristics of the arrangement shown in Fig. 5.

Fig. 7 is a circuit diagram of X-ray apparatus embodying the presentinvention, illustrating a master control device and a cooperatingcontrol device of the type diagrammatically shown in Fig. 1.

Fig. 8 is a cross-section of a modified cooperating control device; and

Fig. 9 is a cross-section of a modified master control device and acooperating control device.

According to Fig. 1 the two circuit-elements 2 and 3 e. g.auto-transformers being provided with taps, are mounted in the basicdevice. The taps of the circuit-elements 2, 3 are connected with thecontact arrangements 4 of the basic device I. The control device 5 isfitted with contact arrangements 6 which correspond and co-operate withthe contact arrangements 4 of the basic device. In the control device 5connections are provided being in contact with its contact'arrangements6 and adapted to a group of typical working conditions. In thearrangement shown in theydrawings these connections are formed byshort-circuit members 'I, 8 and 9 short-circuiting parts of. thecircuit-elements or auto-transformer coils 2 and 3. Each of the controldevices 5 which are intended to be used in conjunction with the basicdevice I possesses other connections and each group of these connectionsis adapted to a group of typical working conditionsworking conditionsfor lungs, skull frontal, heart and so on.

It is of particular advantage that the circuitelements 2, 3 being partlyshort-circuited by the device 5, are not continuously subdivided, but ina geometrical series or progression, since the greatest number ofpermutations, i. e. the finest subdivision results thereby. With aresistance having steps corresponding to the values 1, 2, 4, 8, 16, 3264 subdivisions (from 0 to 63) may be effected.

According to Fig. 2 the basic device or master control device I isfitted with contact arrangements in the form of plug bushes or contactsleeves 4.. The control device 5 shows plug pins 6 co-operating with theplug bushes 4. The control-device 5 is fitted with circuit-elements I3,I4, I5 (resistances, choke-coils, condensers and the like) designed toconform with a group of typical working conditions. The control deviceis formed in the shape of a casing and the circuit-elements I3, l4, I5are mounted in it. According to the drawings the circuit IU of the basicdevice I is closed by the circuit-element I3 of the control device 5. Ina like manner the circuit-elements I l and I5 of the control device 5close the circuits I I and I2 of the basic device I. Therefore, thecircuits Iii, II, l2 are controlled by the circuitelements I3, i l, I5and the current strength of the current of each circuit is determined bythe design of the circuit-elements I3, I4, I5. The circuit-elements I3,I 4, I5 of a control device 5 are adapted to suit the typical workingconditions of a certain case and those of the other control devicesdestined to be used in conjunction with the basic device I, are adaptedto suit the typical working conditions of other cases.

The use of the hitherto generally used mechanical time switches for theproduction of instanfor instance a time switch'based on the loading ordischarging of a condenser. In using such a time switch the elementdetermining the switch times may be lodged in the control device. InFig. 2 the condenser 15 lying in the circuit 12 being the circuit of thetime switch serves for determining the duration of the exposure.Therefore, according to the present invention, circuit-elements for thecircuit of the time switch are fitted into the control device, forinstance condenser, said circuit-elements determining the switch timesand being adapted to suit with the other typical working conditions ofthe control device in hand.

Generally speaking the circuit-elements which according to the presentinvention ought to be mounted into the control device 5 may not only beformed by resistances, coils or condensers, but for the same purpose, i.e. for controlling the basic device i, also relays,. valves, bi-metalstrips and so on may be used.

Regardless of the standardization of the working conditions it. isadvisable to provide regulating devices that are workable by hand and bywhich the working conditions determined by the control device may bevaried within comparatively narrow limits. These regulating devices maybe arranged on the control devices and they permit variation of theWorking conditions Within the limits determined by each of the controldevices so as to adapt them in the best possible manner to thepeculiarities ofthe case in hand. In making a Rontgenogram of a bone itmay be preferable to work with constant voltage at the X-ray tube and tovary the value of milliamperage and exposure time, While in the case ofan exposure on soft parts a regulation of the voltage on the X-ray tubeproduces betterresults. Thus a control device for exposures on softparts may be provided with an additional regulating means workable byhand whichv allows to vary the voltage of the X-ray tube withinrestricted and comparatively narrow limits.

In the case of control devices being provided with several regulatingmeans to beoperated by hand it may be advisable to provide a devicelimiting reciprocally their free movement in such a way that adjustmentscausing overloads of the X-ray tube are prevented thereby. Fig. 3 showsa regulating arrangement of this kind, where at one of the regulationelements a notch-like curved disk and at the other a co-operatingabutment is provided. As to the device according to Fig. 3, mention hasto be made of the following:

For many purposes, more especially for fluoroscopy or radioscopy, a freechoice of the current strength and voltage is often desired. Therefore acontrol device should be used with which both factors may be adjustedseparately. Since the maximum current strength depends on the voltagelying at the X-ray tube, the operating knob it which serves to adjustthe voltage is connected with a curved disk 1! The operating knob it?which serves to adjust the current-strength is provided with a stoporabutment-lever IS. The

limits of the positions of the knob [8 for the regulation of the currentstrength'are therefore determined in each case by the positions ofregulating knob it. When designing the disk I! the load capacity of theX-ray tube is to be taken into account.

In Fig. 9, for example, there are disclosed a master control device (ora portion of the same) i5], having a plurality of contact members MI,

292', 293 and 294', adapted, respectively, to engage contact members29!, 292, 293' and 294 of a cooperating control device I53. An impedance296 is connected to the contact member'ZSI and an impedance 298 to thecontact member 293. Theimpedance 296 is adjustable'by means of a contactarm 29? through the medium of the knob It and the impedance 2% by meansof a contact arm 299 through the medium of the knob IS. The curved diskIll, rigid with the knob I6, limits the range of adjustment of the knobl8. One of these impedances may, for example, control the voltage andthe other the current. As an illustration, the impedance 2% may beconstituted of one of the hereinafter-described resistors 61, 68 and 69,and the impedance 291 one of the herematter-described windings i4, 15and '56.

According toFig. l the basic device is adapted to the simultaneousreception of two control devices 5 and 5. By operating the change-overswitch 28 the two control devices 5 and 5 may be brought to actionsuccessively. The basic device is provided with circuit-elements e. g.windings 2E, 22, 2t, 22' possessing taps. The control devices 5, 5 havecontact arrangements 23, 25, 255 213 co-operating with these taps, saidcontact arrangements being adapted to a group of typical workingconditions; The circuit-elements or windings 2!, 22, 2t, 22' may beshortcircuited more or less by the contact arrangements 23, 24, 23',24'. Moreover, the basic device shows two contact arrangements 25, 25'co-operating with the contact members 26, 26 of the two control devices5, 5. The apparatus according to Fig. lserves for the purpose ofproducing exposures in the manner set forth below by means of an X-raytube with rotatable target. Similar arrangements may, however, also beused for other purposes. The current is led to the contacts or taps ofthe circuit-elements 2 I, 22, 2 l 22 by means of the change-over switch29, whereas the current is led directly to the contact means 25, 25'.The current is led from the taps of the circuit-elements 2 i, 2 i to theheating transformer 2! of the X-ray tube and from the taps of thecircuit-elements or coils 22, 22' to the high tension transformer 28producing the anode potential for the X-ray tube. Of the contactarrangements 25 and 25' only the contact members i a and b leading tothe rotatable anode 30 may be considered. It may be assumed that for thetime being only the control device 5 serving for radioscopy is insertedin the basic device. The rotatable target then stands still to avoidunnecessary wear. Now, after the physician has found the organ he wishesto expose on, the exposure control device 5' is inserted. Thereupon,without the switch 28 being changed over to the control device 5 acurrent flows over the contact arrangement 25' to contact I) and therotatable anode or target begins to rotate, i. e. the exposure isprepared but not yet executed. In the same manner an increased valveheating, the time switch, the diaphragm for scattered radiation, thesensitivity of the instruments and so on may be switched on ready forthe exposure. As .soon as the phase the physician intends to expose ontakes place, by simple changing-over switch 26 from the position markedIto the position marked II the control device 5' is brought into actionand the exposure is effected.

The apparatus according to the present invention further allows tocompensate in a very simple manner the unreliabilities of thedistribution network to which the X-ray apparatus is connected, eitherin respect of the voltage drop' 4 causes that in case of exposures withheavy loads Y the primary voltage decreases and that consequently thevoltage being applied to the X-ray tube, as well as the cathode-heatingvoltage of said tube and thereby the emission current are reduced.Since, as mentioned above, when designing the control devices theintended rate of current strength and voltage are known, the voltagedrop in the distribution network may be taken into account andcompensated for.

Fig. 5 shows the connections of a time switch for the production ofinstantaneous Rontgenograms, the switch times of which depend on theapplied voltage of the line in such a way as to compensate for thevoltage drop occurring in the distribution line or network by increasingthe times of exposuredischarge tube 3! is connected to the outputcircuit of a rectifier-unit 33, the in-put circuit of said unit beingconnected to the distribution line or network. The grid 3 la isconnected by means of a grid-leak resistance 34 with the cathode 3ib.

The working conditions are chosen in such a way that relay 32 attractsits armature and consequently interrupts the current of the X-ray tube.A condenser l5 (see also Fig. 2) is connected to the cathode 3). Thecondenser I5 is connected by means of change-over switch 35 to the D. C.current source 36 of constant voltage, e. g. a battery, and is chargedby it. The charge of condenser l 5 is effected in such a way that thepositive pole is connected to the cathode 3lb. If for the purpose ofexposure the change-over switch 35 is switched from position I toposition'II the negative pole of the condenser I5 is connected with thegrid 3m. Therefore, the anode current is interrupted and the relay 32 isde-energized and thereby closes the anode circuit of the X-ray tube.

The closure can be effected by means of an additional electromagneticrelay or another suitable switch mechanism. The condenser l5 dischargesduring the time of closure over the resistance 34. After an interval oftime being determined by the design of the condenser l5, of theresistance 34 and of the voltage of the battery 36 the voltage or thegrid am has again attained such a value that the anode current of thedischarge tube 3! attracts the relay 32 interrupting thereby the anodecurrent of the X-ray tube.

The anode current strength with which the relay 32 functions, is reachedaccording to the position of the characteristics of the discharge tube3! with different grid voltages. The positions of the characteristicsagain depend on the working voltages i. e. on the voltage of the line orthe in-put voltage of the rectifier-unit 33. With higher primary voltagea characteristic according to A of Fig. 6 results, whereas with lowerprimary voltage a characteristic according to B of Fig. 6 is produced.The current J with which the relay 32 attracts its armature is reachedwith diiferent grid voltages, i. e. after different time intervals,after the condenser 15 has been connected to the grid am. Thus, acompensation of the kind referred to above may be effected and realizedby suitable choice of the type of the grid-controlled valve 3ia, theoperating voltages of same, the current strength of response of" therelay 32, the charge voltage as well as the capacity of the'condenser i5and the value'of the resistance 34. i

It will easily be seen that the above described method of compensationcan be eifected with sufficient accuracy only within the narrow limitsof adefinite type of exposures and therefore is 1 not appropriate whenusing an 'X-ray device to switch certain circuits as for instance thecircuits of the rotatable anode, the cooling pump,

the time switch and'so on in the absenceof current, because with thesedevices a wear 'of' the contacts on switching under current is of noappreciable account. In the embodiment of the invention shown in Fig. 4therefore a device should be provided for avoiding that the controldevice is inserted or taken off, when the change-over switch 20 standsin the position marked I. For that purpose a locking device may becontrolled by the change-over switch 20 preventing the insertion ortaking off of a control device, if the change-over switch 23 is in theswitch-on position of said control device.

The method of manipulation of an X-ray apparatus being fitted with acontrol arrangement as set forth above'is, asa matter of fact,particularly simple. Such a control arrangement dispenseswith thenecessity to use the complicated control means .as practised hithertoincluding complicated switch and control arrangements and causingdiificulties of communication with the staff. The table for radiologicaldiagnosis or'clinoscope'may be combined into a unit with the basicdevice adapted to receive the control devices and the X-ray tube may, ifdesired, be provided at another place of the room. Furthermore, severalbasic devices into which control devices may be inserted at will, may befitted inside or outside the room serving for diagnosis.

Some adjustments cannot be effected directly by means of the controldevices or only in a comparatively complicated manner, for instance thewinding up of the scattered ray diaphragm or the adjustment of theprescribed focus-film distance and so on. These adjustments can be madeeasily noticeable while working by inscriptions on the control device.In order to Verify whether these adjustments are properly eifected thecontrol devices or the basic device may be fitted with a signal thatshows whether the diaphragm was wound up and so on.

The control devices may be distinguished by color, form, inscribedfigures and so on. This is more particularly useful e. g. when it isintended to carry out diagnostics and therapy with the same instrument.

In some cases it is advisable to build up the control devices frominterchangeable, normalized parts, so as to allow their easy alteration.In other cases it is useful, if the control devices optional alteration,so that such an alteration could be efiected only after damaging .a sealor an envelope. This form of execution is particularly suitable, if fromthe side of a producer firm, for the sake of given factory guarantees, afaulty adjustment of an X-ray apparatus is meant to be guarded against.

Referring to Fig. '7, current is supplied to the X-ray apparatus, shownas an X-ray tube 47, from the mains H9 and H3. The X-raytube is providedwith a heating transformer, a voltage transformer, and a furthertransformer for energizing the filament of a rectifying tube I01. Toaccord with Fig. 4, the heating transformer is designated by the numeral21, the volt age transformer by 28, and the further transformer by 30.ing 3'! of the heating transformer 21 extends from a terminal 48,connected to' the main He, by way of a conductor 38, through the primarywinding 31, by way of a conductor 35, and through resistors 69, 58 and51,120 a terminal 49 connected to the main H3. The resistor 57 isconnected to contact terminals 50 and 5!, the resistor 'tflto contactmembers 5| and 52, and the resistor 59 to contact members 52 and 53 of amaster control device. Though, to accord with Fig. 1, this mastercontrol device is designated by the numeral 1, it is shown provided witha number of contact members additional to those designated 50 to '53,indicated at 54 to M.

A control device for cooperating with the master control device I, anddesignated, to conform with Fig. 1, by the numeral 5, is shown providedwith contact members 50' to 6 1', for respectively cooperating with thecontact members 50 to 6 1 of the master control device l.

The cooperating control device 5 is one of many cooperating controldevices that may be substituted, one for another, so as to cooperatewith the master control device I. A further such cooperating controldevice 9| is illustrated in Fig. 8, shown provided with contact members50 to 64", for respectively cooperating with the contact members 50 toE4 of the mastercontrol device I.

In the cooperating control device 5 of Fig. '7, the contact members 5land 52' are shown connected together by a conductor, so as to shortcircuit the resistor 58. In order to show the relation between Fig. 7and Fig. 1, this conductor is designated by the numeral 1. The currentsupplied to the primary winding 31 in order to energize its secondarywinding All of the transformer 21, will thus be reduced by theresistance of the resistors 51 and 59, thereby to heat the cathode ofthe X-ray tube 41 to a proper value. As the contact members and 5!, aswell as the contact members 52' and 53, are not similarly connectedtogether by conductors, the resistors ,6! and 69 will not beshort-circuited. In the cooperating control device 9!, however, thecontact members 50" and 52" are shown connected together by a conductor4!, though the contact members 52" and 55" are not connected together.When the cooperating control device 9! has been juxtaposed intocooperating relation to the master control member I, however, insubstitution for the cooperating control device 5. therefore, with thecontact members 5!!" to 54" in cooperative relation to the contactmembers 55 to 54, the resistors 81 and 58 will both be short-circuitedfrom the circuit of the primary winding 3?, but. the resistor 59 willnot be short-circuited. With the resistors 5i and 58 short-circuited, agreater heating current will be applied to the secondary winding 46ofthe heating transformer 21 and,

The circuit of the primary wind- I therefore, to the filament of theX-ray tube 41. The degree of heating of the cathode of the X-ray tube 41is thus controlled. bysuitable combinations of theresistors 61, 68 and69 through the medium of suitable cooperating control devices, two ofwhich are illustrated at 5 and 9!.

The primary winding 42 of the voltage transformer 28 is connectedinto acircuit extending from a terminal '12, that is connected to the mainHill, by way of a conductor it, through the primary. winding 42, and byway of a conductor 44, to I contact members 19 and 18. When thesecontact members it and T8 are bridged by a contact memher It, thecircuit continues, by way of a conductor 45,.through inductance coils orwindings l6, l5 and l hto a terminal 13, that is connected to the mainH3. The winding '14 is connected to the contact members 54 and 55, thewinding 15 to the contact members 55 and 56, and the winding '15 to thecontact members 5b and 51. The a contact members 54' and 55' are shownconnected together by a conductor that, to correspond to the showing ofFig. 1, is designated by l the numeral 8. When the cooperating controldevice 5 is employed, therefore, as illustrated in r Fig. 7, since thewindings M and 75 become shortcircuited by the conductor 8, thecircuitof the primary winding 42 contains the winding 15 only. Thecontact members 54" and 55" of the: cooperating control device 9|,however, are shown connected together by a conductor 45, and the contactmembers 55 and 5'1" by a conductor 65,

the contact members 55' and 56 being not connected together. When thecooperating control device 9| is employed, therefore, in substitutionfor the cooperating controldevice 5, the coils l4 and 15 will "beshort-circuited, and the circuit.

of the primary winding 42 will contain the coil 15 alone. v

The contact member 11 is actuable intobridging engagement with thecontact members 18 and 19 by means of a coil Bill, the circuit of whichmay be traced from a terminal 8 I that is connected to the main I ill,by way of a conductor 55,'through the coil 85, by way of a conductor H,to aterminal 98. From the terminal 58, the circuit continues through amanually operable switch 83, by Way of a conductor 152, to the contactmember 58. As the contact members 58 and 59' are shown short-circuitedby a conductor that may be desig-,

nated bythe numeral 9, to agree with the showing of Fig.1, the circuitcontinues, from the contact member 58, through the contact members 58'and 59 and the conductors connectingthem,

and'the contact member 59 and, by way of a conductor I63, to a terminal82, that is connected to the main H3. When the cooperating controldevice 5 is employed, therefore, the coil 80 becomes energized merelyupon the manual closing of the switch 83, to effect the bridging of thecontact members 18 and 18 by the contact memare not connected together,this circuit of the coil ill! will remain open, notwithstanding themanual actuation of the switch 83. In such case, the circuit of the coil89 may be under the control of a time switch, designated by the numeral92. This will be described more fully hereinafter.

The circuit of the primary winding 155 of the transformer 35 may betraced from a terminal 85,

to the main II3., The circuit is the same when the cooperating controldevice 9! is employed, except that the contact members 93" and 64" areconnected together by a conductor I I5, instead of through the resistor81. In the former case, therefore, the current applied to the primarywinding I95 will be less than in the latter case.v

I Upon the closing of a line switch (not shown),

therefore, current will be supplied from the mains III) and H3 to theprimary windings 37 and I95 of the respective transformers 21 and 30.

The filament of the rectifying tube I'III will become energized by thesecondary winding I06 of the transformer 39.. If no timing switch 92 isemployed, the switch member 83 will then be manually operated, at theproper time, to energize the coil 89, thus to' actuate the contactmember 17 into bridging engagement with the contact members 18 and I9,whereupon the primary winding 42* of the transformer 28 will becomeenergized. A unidirectional current flow will thereuponbecomeestablished in the circuit of the X-ray tube ;4'I, this circuitincluding the secondary winding III of the transformer 28 and When thecooperating "control device 9| isv employed, as before stated-riot onlyare different currents applied to the primary windings 3?, 42

and I95, but the bridging of the contact members I9 and I8 by thecontactmember'TI will be controlled by the time switch 92, and notmanually by the switch 83. The circuit of the coil 89 may, in this case,be traced from the terminal 8I, by Way of the conductor 66, and throughthe coil 89, to the'terminal- 98, as before. The circuit continues toterminals I29 and I28, when bridged by a switch contact member 96, byway of conductors I23 and I2'I, to the contact member 69. As the contactmembers 60" and 59" are connected together by a conductor I3I, thecircuit continues through the contact members 68 and 68", the conductorI3I, the contact members 59" and59, by Way of the conductor I93, to theterminal 82. The switch contact member 96 is under the control of a coil99. The circuit parameters are so chosen that the normal current throughthe anode circuit of the tube 3! will energize the coil 99 to a degreesuiiicient normally to maintain the'contactmember 96 out of engagementwith the contact members I28 and I29, thus normally preventingenergization of the coil 89. As described hereinafter, the circuit ofthe coil 99 will become closed, however, after a predetermined timeinterval, determined by the time switch 92. l

The time switch is shown provided with a transformer I48 the primarywinding I4I of which is shown connected in a circuit extending from aterminal II2 that is connected to the main III], by way of a conductorI42, through the primary winding I4I to the conductor IZ'I which, asbefore described, is connected to the main H3 through the terminal 82.The time switch 92 is further provided with a glow-cathode tube I2I forcontrolling the tube 3|, provided with the cathode 3Ib, the grid 3Ia,'-and: an

anode I25.

This time' switch 92 is under the control of a condenser which, toaccord'with the showing of Fig. 1, may be designated by the numeral I5,and which isshown-connected between the contact members 9I"and 62".-- I

In one of its positions, the two-way switch 35 connects a contact memberI34 with a 'contact member I35. In its other position, it conheats thecontact member I34 with a contact member I36. In the first-namedposition, the condenser I5 will become charged by a circuit extendingfrom one side of the battery 36, through the contact member I35, theswitch 35, and the contact member I34, by way of a conductor I45,through the contact members 62 and 92", the condenser I5 and the contactmembers 9|" and 8I and, by way of conductors I46 and I41, to the otherside of the battery 35. The

negative pole of the battery 36 is shown connected to the contact member62 and the positive pole to the contact member GI. So poled, thecondenser I5 will, after a predetermined time interval, upon theactuation of the switch 35 to its said other position, impose a chargeupon the grid 3Ia, so as to stop the flow of ourrent throughthe coil 99and permit the bridging of the contact members I28 and I29 by thecontact member 96.- I

The circuit of the condenser I5 and the coil 99 is controlled by amanually operable switch 94. The time switch 92 will not, therefore,operate until a predetermined time has elapsed after the closing of themanually-controlled switch 94.

The resistor 34 is connected between. the oathode BIZ) and the grid em.The purpose of the resistor 34 is to dissipate the energy' in thecondenser I5, thereby gradually reducing the negative charge on the grid3Ia, until it finally obtains a value such as to permit current to flowthrough the tube 3| once more. The coil 99' thereupon becomes againenergized to again actuate the switch 96 out of contact with the contactmembers I28 and I29, more the coil 89. t

Of the two manually controlled switches 83 and 94, the former has beendescribed as employed in connection with the cooperating control member5, and the latter in cooperation with the cooperating control device 9I.In order to make certain'that one only of these switches 83 and 94 maybe operated at a time, they are mechanically connected together by alink I90, which may itself serve as the medium for closing and openingthe respective switches 83 and 94.

We claim:

1. X-ray control apparatus having, in combination, a' master controldevice, and a plurality of separate cooperating control devices adaptedto be manually moved bodily under the control of the operator into andout of cooperative electrical relation to "the master control device,the cooperating control devices each having a group of control elements,the groups of control elements diifering from one another to determinedifierent pluralities of coordinated working factors, each group ofcontrol elements comprising contact means, and the master control devicehaving contact means adapted to be engaged by each of thecontact meansof the respective cooperating control devices when the cooperatingcontrol devices'arein respective cooperative relation to the mastercontrol device to control the oper ation of the X-ray apparatusaccording to the thereby to deenergize once working factors determinedby the respective cooperating control devices.

2. X-ray control apparatus having, in combination, a master controldevice having a plurality of impedances, and a plurality of separatecooperating control devices adapted to be manually moved bodily underthe control of the operator into and out of cooperative electricalrelation to the master control device, the cooperating control deviceseach having a group of control elements, the groups of control elementsdiffering from one another to render selectively different portions ofthe impedances effective in the respective circuits of the X-rayapparatus when the cooperating control devices are respectively incooperative relation to the master control device to control theoperation of the X-ray apparatus according to a plurality ofpredetermined coordinated working factors, the plurality ofpredetermined coordinated Working factors differing according to thegroups of control elements of the respective cooperating controldevices.

3. X-ray control apparatus having, in combination, a master controldevice having a plurality of impedances, and a plurality of separatecooperating control devices adapted to be manually moved bodily underthe control of the operator into and out of cooperative electricalrelation to the master control device, the cooperating control deviceseach having means for selectively short-circuiting different portions ofthe impedances to control the operation of the X-ray apparatus accordingto a plurality of predeter mined coordinated Working factors, theplurality of predetermined coordinated working factors differingaccording to the short-circuited portions of the impedances.

4. X-ray control apparatus having, in combination, a master controldevice having a plurality of impedances provided with'contact membersdividing the impedances into a plurality of portions the impedancevalues of which are in geometric proportion, and a plurality of separatecooperating control devices adapted to be manually moved bodily underthe control of the operator into and out of cooperative electricalrelation to the master control device, the cooperating control deviceseach having cooperating contact members for engaging the first-namedcontact members to render different portions of the impedances effectivein the respective circuits of the X-ray apparatus, thereby to controlthe operation of the X-ray apparatus according to a plurality ofpredetermined coordinated working factors, the plurality ofpredetermined coordinated working factors differing according to theengaged contact members of the cooperating control devices.

5. X-ray control apparatus having, in combination, a master controldevice, and a plurality of separate cooperating control devices adaptedto be manually moved bodily under the control of the operator into andout of cooperative electrical relation to the master control device, thecooperating control devices each having a plurality of impedances, thepluralities of impedances differing from one another to determinedifferent pluralities of predetermined coordinated working factors, andthe master control device having means cooperating With the impedancesof the respective cooperating control devices to control the operationof the X-ray apparatus according to the working factors determined bythe impedances of the respective cooperating control devices. r

6. X-ray control apparatus having, in combination, a master controldevice, a plurality of separate cooperating control devices adapted tobe manually moved bodily under the control of the operator into and outof cooperative electrical relation to the master control device, thecooperating control devices each having a casing and a plurality ofimpedances in the casing, the plurality of impedances differing from oneanother to determine different pluralities of. predetermined coordinatedWorking factors, and the master control device having means cooperatingwith the impedances of the respective cooperating control devices tocontrol the operation of the X-ray apparatus according to the workingfactors determined by the impedances of the respective coop- I cratingcontrol devices.

7. X-ray control apparatus having, in combination, a master controldevice, a plurality of separate cooperating control devices adapted tobe manually moved bodily under the control of the operator into and outof cooperative electrical relation to the master control device, thecooperating control devices each having a group of control elements, thegroups of control elements differing from one another to determinedifferent pluralities of coordinated working factors, the master controldevice having means cooperating with the groups of control elements ofthe re spective cooperating control devices to control the operation ofthe X-ray apparatus according to the working factors determined by therespective cooperating control devices, and means for manually varyingthe working factors corresponding to one or more of the cooperatingcontrol devices within predetermined limits.

8. X-ray control apparatus having, in combination, a master controldevice, a plurality of separate cooperating control devices adapted tobe manually moved bodily under the control of the operator into and outof cooperative electrical relation to the master control device, thecooperating control devices each having a group of control elements, thegroups of control elements differing from one another to determinedifferent pluralities of coordinated working factors, the

master control device having means cooperating with the groups ofcontrol elements of the respective cooperating control devices tocontrol the operation of the X-ray apparatus according to the workingfactors determined by the respective cooperating control devices, andmeans on one or more of the cooperating control devices for manuallyvarying the working factors within predetermined limits.

9. X-ray control apparatus having, in combination, a master controldevice, a plurality of separate cooperating control devices adapted tobe manually moved bodily under the control of the operator into and outof cooperative electrical relation to the master control device, thecooperating control devices each having a group of control elements, thegroups of control elements differing from one another to determinedifferent pluralities of coordinated working factors, the master controldevice having means cooperating with the groups of control elements ofthe respective cooperating control devices to control the operation ofthe X ray apparatus according to the working factors determined by therespective cooperating control devices, a plurality of means on each ofone or more of the cooperating control devices for manually'varying theworking factors within predetermined limits, and means controlling thevariation of another of the plurality of means to prevent overloadingthe X-ray apparatus.

10. X-ray control apparatus having, in combination, a master controldevice, a plurality of separate cooperating control devices adapted tobe manually moved bodily under the control of the operator into and outof cooperative electrical relation to the master control device, thecooperating control devices each having a group of control devices formanually varying the working factors within predetermined limits, and acam controlled by one of the plurality of means and an abutment memberengaged by the cam for limiting the variation of another of theplurality of means to prevent overloading the X-ray apparatus.

11. X-ray control apparatus having, in combination, a master controldevice, a plurality of separate cooperating control devices adapted tobe manually moved bodily under the control of the operator into and outof cooperative electrical relation to the master control device, thecooperating control devices each having a group of control elements, thegroups of control elements differing from one another to determinedifferent pluralities of coordinated working factors, the master controldevice having means cooperating with the groups of control elements ofthe respective cooperating control devices to control the operation ofthe X-ray apparatus according to the working factors determined by therespective cooperating control devices, a normally open switch forcontrolling the operation of the X-ray apparatus to produceinstantaneous exposures, means for electromagnetically controlling theswitch, a space-discharge device for controlling the electromagneticcontrolling means, and means in one or more of the cooperating controldevices for determining predetermined times of operation of thespace-discharge device.

12, X-ray control apparatus having, in combination, a master controldevice, a plurality of separate cooperating control devices adapted tobe manually moved bodily under the control of i the operator into andout of cooperative electrical relation to the master control device, thecooperating control devices each having a group of control elements, thegroups of control elements differing from one another to determine aplurality of coordinated working factors, the master control devicehaving means cooperating with the groups of control elements of therespective cooperating control devices to control the operation of theX-ray apparatus according to the working factors determined by therespective cooperating control devices, a normally open switch forcontrolling the operation of the X-ray apparatus to produceinstantaneous exposures, means for electromagnetically controlling theswitch, a space-discharge device for controlling the electromagneticcontrolling means, means comprising a plurality of elements forcontrolling the flow of current through the space-discharge device, oneof the elements being constituted of acondenser, a source of directcurrent of substantially constant voltage for charging the condenser,and a change-over switch for selectively connecting the condenser to thesource of direct current and to the space-discharge device, whereby theswitch becomes closed during the discharge of the condenser, one of theelements being comprised in one or more of the cooperating controldevices.

13. X-ray control apparatus having, in combination, a master controldevice, a plurality of separate cooperating control devices adapted tobe manually moved bodily under the control of the operator into and outof cooperative electrical relation to the master control device, thecooperating control devices each'having a group of control elements, thegroups of control elements differing from one another to determine aplurality of coordinated working factors, the master control devicehaving means cooperating with the groups of control elements of therespective cooperating control devices to control the operation of theX-ray apparatus according to the working factors determined by therespective cooperating control devices, a switch for controllingtheoperation of the X-ray apparatus to produce instantaneous exposures,means for electromagnetical- 1y controlling the switch, aspace-discharge device for controlling the electromagnetic-controllingmeans and having a cathode, an anode, and means for controlling thecurrent flow between the cathode and the anode, means in one or more ofthe cooperating control devices for determining predetermined times ofoperation of the spacedischarge device, a source of current for theX-ray apparatus, and a rectifier connected to the source for supplyingenergy for the flow of current between the cathode and the anode.

14. X-ray control apparatus having, in combination, a master controldevice, a plurality of separate cooperating control devices adapted tobemanually moved bodily under the control of the operator into and out ofcooperative electrical relation to the master control device, thecooperating control devices each having a group of control elements thegroups of control elements differing from one another to determine aplurality of coordinated working factors, the master control devicehaving means cooperating with the groups of control elements of therespective cooperating control devices to control the operation of theX-ray apparatus according to the working factors determined by therespective cooperating control devices, a normally open switch forcontrolling the operation of the X-ray apparatus to produceinstantaneous exposures, means for electromagnetically controlling theswitch, a spacedischarge device for controlling the electromagneticcontrolling means and having a cathode, an anode, and a controlelectrode, means comprising two elements, namely a resistor and acondenser, for controlling the flow of current through thespace-discharge device, the resistor being connected between the cathodeand the control electrode, a source of direct current of substantiallyconstant voltage for charging the condenser, and a, change-over switchfor selectively connecting the condenser to the source of direct currentand to the control electrode, whereby the switch becomes closed duringthe discharge of the condenser, one of the elements being comprised inone or more of the cooperating control devices.

15. X-ray control apparatus having, in com separate cooperating controldevices adapted to be manually moved bodily under the control of theoperator into and out of cooperative electrical relation to the mastercontrol device, the cooperating control devices each having a group ofcontrol elements, the groups of control elements differing from oneanother to determine a plurality of coordinated working factors, themaster control device having means cooperating with the groups ofcontrol elements of the respective cooperating control devices tocontrol the operation of the X-ray apparatus according to the workingfactors determined by the respective cooperating control devices, themaster device being adapted to cooperate simultaneously "with two. ofthe said cooperating control devices, and a change-over switch forsuccessively connecting the said two cooperating control devices tocontrol successively the X-ray apparatus.

16. X-ray control apparatus having,- in combination, a master controldevice, and a plurality of separate cooperating control devices adaptedto be manually moved bodily under the control of the operator into andout of cooperative electrical relation to the master control device, thecooperating control devices each having a group of control elements, thegroups of control elements differing from one another 'to determinedifferent pluralities of coordinated working factors, and

the master control device having means cooperating with the groups ofcontrol elements of the respective cooperating control devices tocontrol the operation of the X-ray apparatus according to the workingfactors determined by the respective cooperating control devices.

FRIEDRICH DESSAUER. KURT LION.

